Answer:5 Neither: both negative and positive charge are present simultaneously in all solid materials on Earth
Explanation:
When we rub a glass rod with silk cloth then some of the electrons from glass rods are stripped away to the silk cloth. These electrons are loosely bound to the silk rod that is why they easily transferred to silk cloth.
There is no net charge because the charge is induced when we rub the cloth and charge are separated therefore we able to notice these charges.
R=U^2/P=120*120/40=360 ohm
P2=U2^2/R=132*132/360=48.4 w
power increase ratio (48.4-40)/40=21%
Answer:
Ratio of length will be 
Explanation:
We have given time period of the pendulum when length is
is 
And when length is
time period 
We know that time period is given by

So
----eqn 1
And
-------eqn 2
Dividing eqn 2 by eqn 1

Squaring both side

Answer:
a) The schematic illustrating is attached
b) The heat transfer to the heat engine is 2142.86 kJ, the heat transfer from the heat engine is 1392.86 kJ
c) The heat transfer to the heat engine is 1648.35 kJ, the heat transfer from the heat engine is 898.35 kJ
Explanation:
b) The heat transfer to the engine and the heat transfer from the engine to the air is:

Where
W = 750 kJ
n = 35% = 0.25
Replacing:


c) The efficiency of Carnot engine is:

The heat transfer to the heat engine is:

The heat transfer from the heat engine is:

Answer:
A.)1.52cm
B.)1.18cm
Explanation:
angular speed of 120 rev/min.
cross sectional area=0.14cm²
mass=12kg
F=120±12ω²r
=120±12(120×2π/60)^2 ×0.50
=828N or 1068N
To calculate the elongation of the wire for lowest and highest point
δ=F/A
= 1068/0.5
δ=2136MPa
'E' which is the modulus of elasticity for alluminium is 70000MPa
δ=ξl=φl/E =2136×50/70000=1.52cm
δ=F/A=828/0.5
=1656MPa
δ=ξl=φl/E
=1656×50/70000=1.18cm
